ffmpeg parsing h264 fix (part 1)

Job ID: 36197372

Budget: $30 – $250 USD

Need to find the reason of issue with ffmpeg in part of parsing h264, describe it in details with recommended fix steps.

When ffmpeg get live stream from specific device as input, it shows a lot of errors and not processing stream correctly:
[h264 @ 0x327f3210] missing picture in access unit with size xxx

It seems, this is error from libavcodec\h264_parser.c, function parse_nal_units
nal.type of these NALs is 6 (H264_NAL_SEI)

Problematic behavior can be reproduced in this way using attached file:
ffmpeg -i 1.mp4 -vcodec copy -acodec copy -f null /dev/null

Need to find the reason, describe it in details with recommended fix steps.
Second part of the task will be "make fix for source code of ffmpeg 5.1 and 6.0." as new project or separate milestone in this one.